Cigarette heating production line glycerol applying method based on viscosity control

Abstract

The invention discloses a heating cigarette production line glycerol applying method based on viscosity control. The method comprises the following steps: (1) establishing a glycerol solution nonlinear prediction equation taking viscosity as a dependent variable and temperature and mass percentage as independent variables; (2) linearizing the nonlinear prediction equation to obtain a linear equation for controlling viscosity; (3) obtaining a transfer function of the viscosity, the temperature and the mass percentage through Laplace transformation; and (4) designing a solution viscosity control target value, obtaining an actual solution viscosity value at the glycerol applying nozzle, calculating an error between the solution viscosity control target value and the actual solution viscosity value, and adjusting the actual solution viscosity value at the glycerol applying nozzle through a transfer function so as to meet control requirements. According to the heating cigarette production line glycerol application method based on viscosity control, the actual value can be adjusted in real time according to the viscosity design value of the glycerol solution, so that the online application stability of glycerol is improved, and the production quality control of heating cigarette products is supported.

Description

Technical Field

[0001] The invention relates to the technical field of heated cigarettes, and in particular to a glycerol application method for a heated cigarette production line based on viscosity control. Background Art

[0002] With the rapid development of new tobacco, heated cigarettes have gradually become a hot spot in product research and development. Heated cigarettes heat the tobacco core material segment through a special heat source, and produce smoke for consumers to inhale in a non-combustion state. The release characteristics of the smoke determine the sensory quality of the product. At present, the tobacco core materials used to produce smoke are mostly two types: orderly filled thick pulp method reconstituted tobacco leaves and disorderly filled papermaking method reconstituted tobacco leaves. In recent years, in order to enrich the tobacco flavor characteristics of heated cigarette products, cigarette companies have begun to use natural tobacco leaf raw materials as heated cigarette core materials.

[0003] In heated tobacco products, glycerol is the main smoke-generating agent with a variety of properties, such as moisturizing, high activity, antioxidant and low-temperature smoke generation. Glycerol can carry tobacco flavor components at relatively low temperatures (below 300°C), which is crucial to the quality of heated cigarette products. However, due to the extremely high viscosity of glycerol, it is very difficult to apply it to natural tobacco leaf raw materials. At present, the method of applying glycerol to the heated cigarette production line mainly relies on experience. The viscosity is reduced by reducing the mass percentage of glycerol or increasing the temperature, and then the glycerol solution is applied to the tobacco in a certain proportion. However, in this process, there is a lack of stability control over the viscosity of the glycerol solution, which is prone to problems such as over-dilution, over-heating or excessive viscosity of the glycerol solution. This situation will cause large fluctuations in the particle size of the glycerol droplets, affect the accuracy of application, and cannot meet the quality control requirements of heated cigarette production.

[0004] Therefore, it is urgent to establish a propylene glycol application method for a heated cigarette production line based on viscosity control to solve the above technical problems. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a glycerol application method for a heated cigarette production line based on viscosity control, which can adjust the actual value in real time according to the design value of the viscosity of the glycerol solution, thereby improving the stability of glycerol online application to support the production quality control of heated cigarette products.

[0006] The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0007] A method for applying glycerol to a heated cigarette production line based on viscosity control comprises the following steps:

[0008] (1) Establish a nonlinear prediction equation for the viscosity of glycerol solution: take viscosity as the dependent variable, temperature and mass percentage as independent variables, and select the control target values ​​of viscosity, temperature and mass percentage of glycerol solution suitable for the production line;

[0009] (2) Linearizing the nonlinear prediction equation: using the viscosity, temperature and mass percentage control target value of the glycerol solution suitable for the production of heated cigarettes as the working point, linearizing the nonlinear prediction equation of the viscosity of the glycerol solution in step (1) to obtain a linear equation for controlling the viscosity of the glycerol solution;

[0010] (3) Laplace transform: performing Laplace transform on the linear equation in step (2) to obtain the transfer function between the viscosity of the propylene glycol solution and the temperature and mass percentage;

[0011] (4) Establishing and adjusting the online control system: Designing the solution viscosity control target value according to the propylene glycol solution working point in step (2), obtaining the actual value of the solution viscosity at the propylene glycol application nozzle, calculating the error between the solution viscosity control target value and the actual value, and adjusting the actual value of the solution viscosity at the propylene glycol application nozzle through the transfer function in step (3) to meet the control requirements.

[0012] Preferably, in the above technical solution, in step (1), the nonlinear prediction equation of the glycerol solution is a binary differential equation of its viscosity with respect to temperature and mass percentage:

[0013]

[0014] Where z is the predicted viscosity of the propylene glycol solution; k 1 -k 15 is the fitting parameter of the nonlinear prediction equation; x is the temperature of the glycerol solution; y is the mass percentage of glycerol in the glycerol solution; m is 0 or 4, and n is 0 or 3.

[0015] Preferably, in the above technical solution, in step (2), according to the nonlinear prediction equation of viscosity of propylene glycol solution in step (1), the viscosity, temperature and mass percentage control target values ​​suitable for the production line are selected and are respectively denoted as z 0 、x 0 ,y 0 , the mass percentage of propylene glycol y 0 Substituting into the two-variable differential equation, we get the one-variable differential equation of solution viscosity z with respect to temperature x:

[0016]

[0017] Where z is the predicted viscosity of the propylene glycol solution; k 1 -k 15is the fitting parameter of the nonlinear prediction equation; x is the temperature of the glycerol solution; y is the temperature of the glycerol solution; 0 is the target value for the mass percentage of glycerol; m is 0 or 4, and n is 0 or 3;

[0018] When the temperature x approaches the control target value x 0 When , the linear equation of viscosity z of propylene glycol solution with respect to temperature x is as follows:

[0019] z(x)=z(x 0 )+z′(x 0 )(xx 0 );

[0020] Rearranging the terms in the equation gives:

[0021] z(x 0 )-z(x)=z′(x 0 )(x 0 -x);

[0022] Let the temperature error e x =x 0 -x, viscosity error e z =z 0 -z, substitute the linear equation of the viscosity (z) of propylene glycol solution with respect to temperature (x) to obtain the linear equation of temperature error and viscosity error:

[0023]

[0024] Preferably, in the above technical solution, in step (3), the linear equation of temperature error and viscosity error is Laplace transformed:

[0025]

[0026] Assume that the system input is the error E between the viscosity control target value and the actual value of the propylene glycol solution. z(S) The system output is the error E between the target value and the actual value of the propylene glycol solution temperature control. x(S) , the transfer function between the viscosity error and temperature error of propylene glycol solution is obtained:

[0027]

[0028] Preferably, in the above technical solution, in step (4), the transfer function in step (3) is used to establish an online control system for the viscosity of the glycerol solution (see Figure 7 ), preferably, a PI controller is introduced into the system, and appropriate proportional and integral gains are selected to further improve the control performance of the system, Figure 7 In, Z 0(S) is the target value for viscosity control of glycerol solution; E z(S)G is the error between the target value and the actual value of the viscosity control of glycerol solution; (S) is the transfer function between the viscosity of propylene glycol solution and temperature and mass percentage; E x(S) is the error between the target value and the actual value of the glycerol solution temperature control; Z (S) It is the actual value of the viscosity of propylene glycol solution.

[0029] Preferably, in the above technical solution, the actual value of the viscosity of the glycerol solution is detected by an oscillating or rotating online viscometer, and the viscosity analysis range of the online viscometer is required to include 0 to 20000 cP, and the viscosity resolution is ≤0.5 cP.

[0030] Preferably, in the above technical solution, the viscosity analysis range of the online viscometer is required to include 0 to 15000 cP, and the viscosity resolution is ≤ 0.1 cP.

[0031] The above technical solution of the present invention has the following beneficial effects:

[0032] (1) By establishing a glycerol application method for a heated cigarette production line based on viscosity control, the viscosity of the glycerol solution can be adjusted in real time to improve the stability of glycerol online application.

[0033] (2) Nonlinear prediction equations and transfer functions are used to adjust the solution viscosity at the glycerol application nozzle to reduce the fluctuation of glycerol droplet size and thus improve the accuracy of glycerol application.

[0034] (3) By setting appropriate control target values ​​and adjusting the viscosity of the propylene glycol solution according to the actual value error, the quality control level of heated cigarette products can be improved.

[0035] (4) The transfer function is obtained by linearizing the nonlinear prediction equation and Laplace transform, which can realize automatic adjustment of the solution viscosity at the propylene glycol application nozzle and improve the efficiency and stability of the production line. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0037] Figure 1 The present invention is a flow chart of a glycerol application method for a heated cigarette production line based on viscosity control.

[0038] Figure 2 It is a data surface graph of propylene glycol temperature, mass percentage and corresponding viscosity of propylene glycol aqueous solution. Note: The yellow dots are the measured values ​​of propylene glycol viscosity.

[0039] Figure 3This is the actual value control curve of the viscosity online control system when the mass percentage of glycerol is 60% and the temperature is 20°C and the viscosity target value is 10.91cP.

[0040] Figure 4 This is the actual value control curve of the viscosity online control system when the mass percentage of glycerol is 85% and the temperature is 20°C and the viscosity target value is 119.33 cP.

[0041] Figure 5 This is the actual value control curve of the viscosity online control system when the mass percentage of glycerol is 75% and the temperature is 30°C and the viscosity target value is 21.62cP.

[0042] Figure 6 This is the actual value control curve of the viscosity online control system when the mass percentage of glycerol is 100% and the temperature is 70°C and the viscosity target value is 49.62cP.

[0043] Figure 7 Schematic diagram of the online control system for the viscosity of propylene glycol solution.

[0044] Figure 8 Schematic diagram of an online control system for the viscosity of a propylene glycol solution established in Example 1.

[0045] Fig. 9 Schematic diagram of establishing an online control system for the viscosity of a propylene glycol solution in Example 2.

[0046] Fig.10 Schematic diagram of establishing an online control system for the viscosity of a propylene glycol solution in Example 3.

[0047] Fig.11 Schematic diagram of an online control system for the viscosity of a propylene glycol solution established in Example 4. DETAILED DESCRIPTION

[0048] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0049] Unless otherwise specified, the reagents used in this application are all commercially available or obtained through commercial channels, or can be prepared by referring to existing chemical methods.

[0050] Example 1

[0051] A method for applying glycerol to a heated cigarette production line based on viscosity control (eg Figure 1 The method comprises the following steps:

[0052] (1) With viscosity as the dependent variable and temperature and mass percentage as independent variables, a binary nonlinear prediction equation for glycerol aqueous solution is established. When the mass percentage of glycerol (y) is in the range of 0% to 80% and the temperature of the glycerol aqueous solution (x) is in the range of 0℃ to 30℃ (excluding 30℃), the viscosity of the glycerol aqueous solution conforms to the following equation:

[0053]

[0054] Wherein, z is the predicted value of the viscosity of the glycerol aqueous solution; x is the temperature of the glycerol aqueous solution; and y is the mass percentage of glycerol in the glycerol aqueous solution.

[0055] (2) According to the nonlinear prediction equation of viscosity of glycerol aqueous solution, the working parameter table of glycerol aqueous solution is established, as shown in Table 1. It can be calculated from Table 1 that the correlation coefficient between the predicted result and the actual result is 0.999992.

[0056] Table 1 Measured and predicted values ​​of viscosity of glycerol aqueous solution with glycerol mass percentage between 0% and 80% and temperature between 0℃ and 30℃

[0057]

[0058]

[0059] (3) The working point of the glycerol solution during the production of heated cigarettes is selected as follows: the mass percentage of glycerol is 60%, the temperature is 20°C, and the viscosity is 10.91 cP.

[0060] (4) Substituting the mass percentage of glycerol at the working point into the binary nonlinear prediction equation of the viscosity of the glycerol aqueous solution, a univariate nonlinear prediction equation of the viscosity with respect to temperature is obtained:

[0061]

[0062] (5) The viscosity z(x) is differentiated with respect to temperature x to obtain the first-order derivative equation of viscosity with respect to temperature z'(x). Substituting the temperature of the working point into z'(x), we obtain:

[0063] z′(x 0 )=-0.4758

[0064] (6) Let the system input be the error E between the control target value and the actual value of the viscosity of the propylene glycol solution z(S) The system output is the error E between the control target value and the actual value of the propylene glycol solution temperature x(S) , the transfer function between the viscosity error and temperature error of propylene glycol solution is obtained:

[0065]

[0066] (7) Using the transfer function G (S) Establish an online control system for the viscosity of glycerol solution (see Figure 8 ):

[0067] When the mass percentage of glycerol is 60% and the temperature is 20°C, the actual value control curve of the viscosity online control system when the viscosity target value is 10.91 cP is shown in Figure 3 . The above viscosity online control system is used in the production process of heated cigarettes. The actual viscosity of the glycerol solution at the nozzle can reach the control target value within 5 seconds, realizing the continuous control of the viscosity value of the glycerol solution at the nozzle. The system has no overshoot and solves the problem of slow cooling of the glycerol solution in the insulation tank on the production line.

[0068] Example 2

[0069] A method for applying glycerol to a heated cigarette production line based on viscosity control (eg Figure 1 The method comprises the following steps:

[0070] (1) With viscosity as the dependent variable and temperature and mass percentage as independent variables, a binary nonlinear prediction equation for glycerol aqueous solution is established. When the mass percentage of glycerol (y) is in the range of 80% to 100% (excluding 80%) and the temperature of glycerol aqueous solution (x) is in the range of 0℃ to 30℃ (excluding 30℃), the viscosity of glycerol aqueous solution conforms to the following equation:

[0071]

[0072] Wherein, z is the predicted value of the viscosity of the glycerol aqueous solution; x is the temperature of the glycerol aqueous solution; and y is the mass percentage of glycerol in the glycerol aqueous solution.

[0073] (2) According to the nonlinear prediction equation of viscosity of glycerol aqueous solution, the working parameter table of glycerol aqueous solution is established, as shown in Table 2. It can be calculated from Table 2 that the correlation coefficient between the predicted result and the actual result is 0.999994.

[0074] Table 2 Measured and predicted values ​​of viscosity of glycerol aqueous solution with glycerol mass percentage between 80% and 100% and temperature between 0℃ and 30℃

[0075]

[0076]

[0077] (3) The working point of the glycerol solution during the production of heated cigarettes is selected as follows: the mass percentage of glycerol is 85%, the temperature is 20°C, and the viscosity is 119.33 cP.

[0078] (4) Substituting the mass percentage of glycerol at the working point into the binary nonlinear prediction equation of the viscosity of the glycerol aqueous solution, a univariate nonlinear prediction equation of the viscosity with respect to temperature is obtained:

[0079]

[0080] (5) The viscosity z(x) is differentiated with respect to temperature x to obtain the first-order derivative equation of viscosity with respect to temperature z'(x). Substituting the temperature of the working point into z'(x), we obtain:

[0081] z′(x 0 )=-6.6425

[0082] (6) Let the system input be the error E between the control target value and the actual value of the viscosity of the propylene glycol solution z(S) The system output is the error E between the control target value and the actual value of the propylene glycol solution temperature x(S) , the transfer function between the viscosity error and temperature error of propylene glycol solution is obtained:

[0083]

[0084] (7) Using the transfer function G (S) Establish an online control system for the viscosity of glycerol solution (see Fig. 9 ):

[0085] When the mass percentage of glycerol is 85% and the temperature is 20°C, the actual value control curve of the viscosity online control system when the viscosity target value is 119.33 cP is shown in Figure 4 . The above viscosity online control system is used in the production process of heated cigarettes. The actual viscosity of the glycerol solution at the nozzle can reach the control target value within 5 seconds, realizing the continuous control of the viscosity value of the glycerol solution at the nozzle. The system has no overshoot and solves the problem of slow cooling of the glycerol solution in the insulation tank on the production line.

[0086] Example 3

[0087] A method for applying glycerol to a heated cigarette production line based on viscosity control (eg Figure 1 The method comprises the following steps:

[0088] (1) With viscosity as the dependent variable and temperature and mass percentage as independent variables, a binary nonlinear prediction equation for glycerol aqueous solution is established. When the mass percentage of glycerol (y) is in the range of 0% to 80% and the temperature of glycerol aqueous solution (x) is in the range of 30°C to 100°C, the viscosity of glycerol aqueous solution conforms to the following equation:

[0089]

[0090] Wherein, z is the predicted value of the viscosity of the glycerol aqueous solution; x is the temperature of the glycerol aqueous solution; and y is the mass percentage of glycerol in the glycerol aqueous solution.

[0091] (2) According to the nonlinear prediction equation of viscosity of glycerol aqueous solution, the working parameter table of glycerol aqueous solution is established, as shown in Table 3. It can be calculated from Table 3 that the correlation coefficient between the predicted result and the actual result is 0.999994.

[0092] Table 3 Measured and predicted values ​​of viscosity of glycerol aqueous solution with glycerol mass percentage between 0% and 80% and temperature between 30℃ and 100℃

[0093]

[0094]

[0095]

[0096] (3) The working point of the glycerol solution during the production of heated cigarettes is selected as follows: the mass percentage of glycerol is 75%, the temperature is 30°C, and the viscosity is 21.62 cP.

[0097] (4) Substituting the mass percentage of glycerol at the working point into the binary nonlinear prediction equation of the viscosity of the glycerol aqueous solution, a univariate nonlinear prediction equation of the viscosity with respect to temperature is obtained:

[0098]

[0099] (5) The viscosity z(x) is differentiated with respect to temperature x to obtain the first-order derivative equation of viscosity with respect to temperature z'(x). Substituting the temperature of the working point into z'(x), we obtain:

[0100] z′(x 0 )=-1.1235

[0101] (6) Let the system input be the error E between the control target value and the actual value of the viscosity of the propylene glycol solution z(S) The system output is the error E between the control target value and the actual value of the propylene glycol solution temperature x(S) , the transfer function between the viscosity error and temperature error of propylene glycol solution is obtained:

[0102]

[0103] (7) Using the transfer function G (S) Establish an online control system for the viscosity of glycerol solution (see Fig.10 ):

[0104] When the mass percentage of glycerol is 75% and the temperature is 30°C, the actual value control curve of the viscosity online control system when the viscosity target value is 21.62 cP is shown in Figure 5 . The above viscosity online control system is used in the production process of heated cigarettes. The actual viscosity of the glycerol solution at the nozzle can reach the control target value within 5 seconds, realizing the continuous control of the viscosity value of the glycerol solution at the nozzle. The system has no overshoot and solves the problem of slow cooling of the glycerol solution in the insulation tank on the production line.

[0105] Example 4

[0106] A method for applying glycerol to a heated cigarette production line based on viscosity control (eg Figure 1 The method comprises the following steps:

[0107] (1) With viscosity as the dependent variable and temperature and mass percentage as independent variables, a binary nonlinear prediction equation for glycerol aqueous solution is established. When the mass percentage of glycerol (y) is in the range of 80% to 100% (excluding 80%) and the temperature of the glycerol aqueous solution (x) is in the range of 30°C to 100°C, the viscosity of the glycerol aqueous solution conforms to the following equation:

[0108]

[0109] Wherein, z is the predicted value of the viscosity of the glycerol aqueous solution; x is the temperature of the glycerol aqueous solution; and y is the mass percentage of glycerol in the glycerol aqueous solution.

[0110] (2) According to the nonlinear prediction equation of viscosity of glycerol aqueous solution, the working parameter table of glycerol aqueous solution is established, as shown in Table 4. It can be calculated from Table 4 that the correlation coefficient between the predicted result and the actual result is 0.999997.

[0111] Table 4 Measured and predicted values ​​of viscosity of glycerol aqueous solution with glycerol mass percentage between 80% and 100% and temperature between 30℃ and 100℃

[0112]

[0113]

[0114] (3) The working point of the glycerol solution during the production of heated cigarettes is selected as follows: the mass percentage of glycerol is 100%, the temperature is 70° C., and the viscosity is 49.62 cP.

[0115] (4) Substituting the mass percentage of glycerol at the working point into the binary nonlinear prediction equation of the viscosity of the glycerol aqueous solution, a univariate nonlinear prediction equation of the viscosity with respect to temperature is obtained:

[0116]

[0117] (5) The viscosity z(x) is differentiated with respect to temperature x to obtain the first-order derivative equation of viscosity with respect to temperature z'(x). Substituting the temperature of the working point into z'(x), we obtain:

[0118] z′(x 0 )=-2.2494

[0119] (6) Let the system input be the control target value and actual value error of the viscosity of propylene glycol solution Ez(S) The system output is the error E between the control target value and the actual value of the propylene glycol solution temperature x(S) , the transfer function between the viscosity error and temperature error of propylene glycol solution is obtained:

[0120]

[0121] (7) Using the transfer function G (S) Establish an online control system for the viscosity of glycerol solution (see Fig.11 ):

[0122] When the mass percentage of glycerol is 100% and the temperature is 70°C, the actual value control curve of the viscosity online control system when the viscosity target value is 49.62 cP is shown in Figure 6 . The above viscosity online control system is used in the production process of heated cigarettes. The actual viscosity of the glycerol solution at the nozzle can reach the control target value within 5 seconds, realizing the continuous control of the viscosity value of the glycerol solution at the nozzle. The system has no overshoot and solves the problem of slow cooling of the glycerol solution in the insulation tank on the production line.

[0123] Although the present invention has been disclosed as above by the embodiments, it is not intended to limit the present invention. Any person skilled in the art may make various choices and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention is limited by the claims and their equivalents.

Claims

1. A method for applying glycerol to a heated cigarette production line based on viscosity control, characterized in that: The following steps are involved: (1) Establish a nonlinear prediction equation for the viscosity of glycerol solution: take viscosity as the dependent variable, temperature and mass percentage as independent variables, and select the control target values ​​of viscosity, temperature and mass percentage of glycerol solution suitable for the production line; (2) Linearizing the nonlinear prediction equation: using the viscosity, temperature and mass percentage control target value of the glycerol solution suitable for the production of heated cigarettes as the working point, linearizing the nonlinear prediction equation of the viscosity of the glycerol solution in step (1) to obtain a linear equation for controlling the viscosity of the glycerol solution; (3) Laplace transform: performing Laplace transform on the linear equation in step (2) to obtain the transfer function between the viscosity of the propylene glycol solution and the temperature and mass percentage; (4) Establishing and adjusting the online control system: Designing the solution viscosity control target value according to the propylene glycol solution working point in step (2), obtaining the actual value of the solution viscosity at the propylene glycol application nozzle, calculating the error between the solution viscosity control target value and the actual value, and adjusting the actual value of the solution viscosity at the propylene glycol application nozzle through the transfer function in step (3) to meet the control requirements.

2. The glycerol application method for a heated cigarette production line based on viscosity control according to claim 1, characterized in that: In step (1), the nonlinear prediction equation of the propylene glycol solution is a binary differential equation of its viscosity with respect to temperature and mass percentage fraction: Where z is the predicted viscosity of the propylene glycol solution; k1-k 15 is the fitting parameter of the nonlinear prediction equation; x is the temperature of the glycerol solution; y is the mass percentage of glycerol in the glycerol solution; m is 0 or 4, and n is 0 or 3.

3. The glycerol application method for a heated cigarette production line based on viscosity control according to claim 1, characterized in that: In step (2), according to the nonlinear prediction equation of glycerol solution viscosity in step (1), the viscosity, temperature and mass percentage control target values ​​suitable for the production line are selected and recorded as z0, x0, and y0 respectively. The mass percentage of glycerol y0 is substituted into the two-variable differential equation to obtain the one-variable differential equation of solution viscosity z with respect to temperature x: Where z is the predicted viscosity of the propylene glycol solution; k1-k 15 is the fitting parameter of the nonlinear prediction equation; x is the temperature of the glycerol solution; y0 is the control target value of the glycerol mass percentage; m is 0 or 4, and n is 0 or 3; When the temperature x is close to the control target value x0, the linear equation of the viscosity z of the propylene glycol solution with respect to the temperature x is as follows: z(x)=z(x0)+z′(x0)(x-x0); Rearranging the terms in the equation gives: z(x0)-z(x)=z′(x0)(x0-x); Let the temperature error e x =x0-x, viscosity error e z =z0-z, substitute into the linear equation of viscosity (z) of propylene glycol solution with respect to temperature (x), and obtain the linear equation of temperature error and viscosity error:

4. The glycerol application method for a heated cigarette production line based on viscosity control according to claim 1, characterized in that: In step (3), the linear equation of temperature error and viscosity error is Laplace transformed: Assume that the system input is the error E between the viscosity control target value and the actual value of the propylene glycol solution. z(S) The system output is the error E between the target value and the actual value of the propylene glycol solution temperature control. x(S) , the transfer function between the viscosity error and temperature error of propylene glycol solution is obtained:

5. The glycerol application method for a heated cigarette production line based on viscosity control according to claim 1, characterized in that: In step (4), the transfer function in step (3) is used to establish an online control system for the viscosity of the propylene glycol solution. Preferably, a PI controller is introduced into the system, and appropriate proportional and integral gains are selected to further improve the control performance of the system.

6. The glycerol application method for a heated cigarette production line based on viscosity control according to claim 5, characterized in that: The actual value of the viscosity of the glycerol solution is detected by an oscillating or rotating online viscometer, and the viscosity analysis range of the online viscometer is required to include 0 to 20,000 cP, and the viscosity resolution is ≤ 0.5 cP.

7. The glycerol application method for a heated cigarette production line based on viscosity control according to claim 6, characterized in that: The viscosity analysis range of the online viscometer is required to include 0 to 15000 cP, and the viscosity resolution is ≤ 0.1 cP.

Images